“The general rule for proper positioning is to have your baby sitting with knees at approximately the same level as their hips. This position allows the baby’s weight to be comfortably distributed through their back, bottom and legs, with no pressure hot spots.
The dangling position you see at left creates an area of high pressure in the baby’s crotch, and at the base of his/her spine. The heavier the baby, the more pressure on crotch/spine.
If a baby carrier doesn’t allow your baby to be in a spread seated position, then skip it!”
Baby Carrier Comparison Chart at theportablebaby.com